NEW YORK — Planned Parenthood said Wednesday that it received more than $400,000 from 6,000 donors in the 24 hours after news broke that its affiliates would be losing grants for breast screenings from the Susan G. Komen for the Cure breast-cancer foundation.

Rates of women who are opting for preventive mastectomies, such as Angeline Jolie, have increased by an estimated 50 percent in recent years, experts say. But many doctors are puzzled because the operation doesn't carry a 100 percent guarantee, it's major surgery -- and women have other options, from a once-a-day pill to careful monitoring.

Komen, meanwhile, incurred heated criticism from some members of Congress, numerous liberal advocacy groups and some newspaper editorial writers. But it was applauded by many conservative religious and anti-abortion groups that abhor Planned Parenthood for its role as the leading U.S. abortion provider.

Planned Parenthood says the funding cutoff was a result of Komen succumbing to pressure from anti-abortion activists. Komen, in a statement issued Wednesday evening, denied that politics played a role and reiterated that its decision was based on newly adopted criteria for issuing grants.

The criteria bar grants to any organization that's under local, state or federal investigation. Planned Parenthood is being investigated for alleged financial improprieties by a Republican congressman acting with the encouragement of anti-abortion groups.

"We regret that these new policies have impacted some long-standing grantees, such as Planned Parenthood, but want to be absolutely clear that our grant-making decisions are not about politics," the Komen statement said.

It pledged to ensure that women who need breast-health services can still have access to them.

Dr. Eric Winer, a breast cancer specialist at Dana-Farber Cancer Institute in Boston who is chairman of Komen's scientific advisory council, said he was confident that breast-screening availability would not be jeopardized.

"The last thing in the world that anyone at Komen wants to do ... is to decrease the resources that are available to those women," he said.

Nonetheless, some members of Komen's nationwide network were unsettled.

The Komen affiliate in Connecticut posted a notice on its website saying it has enjoyed a "great partnership" with Planned Parenthood of Southern New England and noting that the funding decision was made at Komen's national headquarters.

"We understand, and share, in the frustration around this situation," the notice said. "We hope that any investigation prohibiting Planned Parenthood from receiving Komen grants is promptly resolved."

Planned Parenthood said the Komen grants totaled roughly $680,000 last year and $580,000 the year before, going to 19 of its affiliates for breast-cancer screening and other breast-health services. According to Planned Parenthood, its health centers performed more than 4 million breast exams over the past five years, including nearly 170,000 as a result of Komen grants.

Andrea Hagelgans, a Planned Parenthood spokeswoman, said the organization was grateful for the outpouring of support since Tuesday evening, when The Associated Press first reported Komen's decision.

"People respond powerfully when they see politics interfering with women's health," she said. "These donations will continue to help expand Planned Parenthood's critical health care services nationwide, especially those affiliates impacted by the Komen cuts."

Several members of Congress who support abortion rights voiced dismay at the grant cutoff.

"I was perplexed and troubled to see the decision by Susan G. Komen for the Cure to cut off funding for lifesaving breast cancer screenings through Planned Parenthood because of a political witch hunt by House Republicans," said Sen. Barbara Boxer, D-Calif. "I truly hope that they will reconsider this decision and put the needs of women first."

The progressive group MoveOn.org launched an online petition calling on Komen to maintain its grants to Planned Parenthood. It said 60,000 people had signed in a matter of hours.

Komen won praise from anti-abortion activists such as Charmaine Yoest, president of Americans United for Life.

"The work of the Komen Foundation has lifesaving potential and should not be intertwined with an industry dealing in death," said Yoest, a breast-cancer survivor.

She said she had stopped running in Komen's Race for the Cure because of its ties with Planned Parenthood, but "in the future, I'll be racing with them to support this courageous decision."

Komen, based in Dallas and founded in 1982, has invested more than $1.9 billion since then in research, health services and advocacy while becoming the largest breast-cancer charity in the nation. Its Race for the Cure fundraising events have become a global phenomenon.

Editorials about Komen's decision were published by several newspapers.

"Komen caved to political pressure," wrote editorial writer Tod Robberson in the Dallas Morning News. "The next time Komen for the Cure comes asking us for an editorial supporting one of their local events, I'm going the think twice."

The Star-Ledger in New Jersey took a more nuanced view.

"It's hard to see who the winners are in this mess," it wrote. "As so often happens when their bodies become a political battleground, women ultimately lose."

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